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Wave-induced transport of non-buoyant microplastic particles: Phase-resolved experiments and excess-Shields scaling
No full textThe present study investigates the bed-load dynamics of non-buoyant microplastic particles subjected to wave forcing, with emphasis on the phase-resolved relationship between particle motion and near-bed hydrodynamics. Specifically, five groups of PLA particles, differing in shape and density, were tested in a wave flume under five regular wave conditions representative of intermediate-depth coastal environments. Based on high quality video analysis, particle mobilisation occurred when the modified Shields parameter for plastics exceeded the incipient-motion threshold derived from previous work. The experiments highlighted a residual onshore drift that depends on the particle characteristics and increases with wave steepness, resulting from asymmetries in the near-bed velocity field. For the first time, a link has been established between the phase-resolved particle velocity, normalised by the near-bed flow velocity, and the ratio of the modified Shields number for plastics to the incipient motion threshold, revealing a clear non-linear dependence between particle mobility and the applied force
Labour Migration and Policy Negotiations: the 1976Tunisia-EEC Cooperation Agreement and its Impact
No full textThe article analyses the social dimension of cooperation, with particularattention to labour mobility, between Tunisia and the EuropeanEconomic Community within the framework of the 1976 cooperationagreement, which emerged as part of the Global Mediterranean Policy.The aim of the article is to offer a perspective from a Global South coun-try, moving beyond the Eurocentric narrative of North–South migration,and to show how Tunisia demonstrated its own capacity for agency,even while operating within an increasingly restrictive internationalcontext. Within this broader strategy of North–South cooperation,Tunisia sought to expand the scope of its dialogue with the EuropeanCommunity. Tunis’s objective was not only to alleviate domestic socialtensions and enhance human capital, but also to legitimise a broaderdemand for European involvement in the country’s development. Thetransfer of skills, regulation of migration flows, social protection forworkers and shared development became the central pillars of theTunisian proposal. In this way, the Tunisian government sought to seizethe political momentum generated by the Global Mediterranean Policyto promote an alternative model of cooperation that reflected its ownaspirations
Observation of perfect absorption in hyperfine levels of molecular spins with hermitian subspaces
No full textWe investigate Perfect Absorption (PA) of radiation, in which incoming energy is entirely dissipated, in a system consisting of molecular spin centers coherently coupled to a planar microwave resonator operated at milliKelvin temperature and in the single photon regime. This platform allows us to fine tune the spin-photon coupling and to control the effective dissipation of the two subsystems towards the environment, thus giving us the opportunity to span over a wide space of parameters. Our system can be effectively described by a non-Hermitian Hamiltonian exhibiting distinct Hermitian subspaces. We experimentally show that these subspaces, linked to the presence of PA, can be engineered through the resonator-spin detuning, which controls the composition of the polaritons in terms of photon and spin content. In such a way, the required balance between the feeding and the loss rates is effectively recovered even in the absence of PT-symmetry. We show that Hermitian subspaces influence the overall aspect of coherent spectra of cavity QED systems and enlarge the possibility to explore non-Hermitian effects in open quantum systems. We finally discuss how our results can be potentially exploited for applications, in particular as single-photon switches and modulators
Piattaforme digitali, il ruolo di datore e l’esercizio del potere disciplinare
No full textIl saggio esamina i presupposti della potestà sanzionatoria delle piattaforme alla luce delle dinamiche del sistema di rating ed approfondisce la disciplina contenuta nella direttiva UE sul miglioramento delle condizioni di lavoro delle piattaforme digitali, evidenziando che le misure della direttiva relative al potere disciplinare, che si affiancano alle garanzie già previste dall’ordinamento nazionale, celano problematiche dalla soluzione non agevole, che andranno analizzate in sede di recepimento della direttiva
A newly isolated Streptomyces nigra strain for the biotechnological production of melanin
No full textMelanins are pigments widely distributed in microbial, plant, and animal kingdoms. Their UV-visible light shielding capacity, metal chelation ability, antioxidant, and antimicrobial properties make these pigments suitable for different industrial applications like in cosmetic and bioremediation fields. The actual manufacturing process relies on the extraction from animal tissues like the ink of Sepia officinalis and/or on synthetic chemical procedures. Streptomycetes might be the ideal candidates for the development of biotechnological processes of melanin production due to their ability to produce pigments as secondary metabolites, extracellularly released. Here, a new strain of Streptomyces nigra, capable of efficiently producing eumelanin, was isolated from soil samples in Messina, Sicily, Italy, and characterized first by 16S rRNA analysis and then by whole genome sequencing, with a complete gene clusters analysis. The strain ability of growing and producing melanin was tested on four media, including newly formulated ones, and by also optimizing temperature and pH conditions of growth, a melanin production of 2.45 ± 0.01 g/L was reached. The pigment, once produced under the optimal conditions, was purified and characterized by UV-visible, FT-IR, NMR, and EPR spectroscopy, revealing an eumelanin-like structure
Foot Pathologies in Dairy Cows: Preliminary Data on Clinical Assessment, Blood Biochemistry Analysis, and Infrared Thermography
No full textFoot diseases represent a major cause of impaired welfare and reduced productivity in dairy ruminants. This pilot study aimed to evaluate the clinical progression of foot lesions in dairy cattle by combining clinical examination with hematochemical analyses and infrared thermography of foot (central zone, R1; interdigital area, R2; lateral claw, R3; medial claw, R4), in order to assess the effectiveness of therapeutic interventions and the evolution of inflammation over time. The study involved dairy cows affected by different foot disorders that underwent functional and therapeutic trimming. Ten lactating cows with hoof diseases (DG) were tested and 5 healthy animals (CG) were selected to serve as a control group. The animals were evaluated and sampled (blood sampling and acquisition of thermographic foot images) at three different time points: clinical diagnosis of the foot pathology (T0), 24 h (T1) and 10 days (T2) after treatment. Higher neutrophils, lymphocytes, platelets, alpha 1-(p < 0.05) and alpha 2-fraction values were found in diseased subjects compared to healthy ones at T0 (p < 0.05). Thermography highlighted significantly higher foot thermal values in animals with lesions than in healthy animals (p < 0.01), especially at T0. Animals affected by hoof diseases showed lower foot temperature values at T1 compared to T0 and T2 (p < 0.001). Though the small sample size and the short observation period limited the possibility of extending the results to the entire cow population, the infrared thermography proved to be a valuable non-invasive tool for detecting active lesions and monitoring healing, with higher temperatures corresponding to inflamed areas and a progressive normalization after treatment. The combined evaluation of clinical signs, systemic inflammatory markers and thermographic patterns provided an integrated perspective on the progression of foot diseases
Real-world management of familial hypercholesterolemia in paediatric patients: a 3-year follow-up from the LIPIGEN registry
No full textBackground and aim: Familial hypercholesterolemia (FH) is a common genetic disorder characterized by elevated low-density lipoprotein cholesterol (LDL-C) from early life, significantly increasing lifetime risk of atherosclerotic cardiovascular disease. Early identification and initiation of lipid-lowering therapy (LLT) are crucial. This study aimed to describe the timing, pharmacological approach, and early outcomes of LLT initiation in children and adolescents with FH from the Italian LIPIGEN registry. Methods: We analysed 341 paediatric FH patients who were untreated at baseline and had follow-up data within 3 years. Data included clinical features, LDL-C levels, genetic testing results, and treatment patterns. Outcomes included time to LLT initiation, type of therapy, LDL-C reduction, and achievement of guideline-recommended goals. Results: Mean age at baseline was 10.8 years. At the end of the first year of follow-up, 51.6% initiated LLT, increasing to 78.9% after 3 years (mean age at treatment initiation: 10.9 years), with earlier initiation among those with higher baseline LDL-C. Statins were the most used agents (43.9%), especially in children ≥8 years, followed by combination statin-ezetimibe (11.5%). Nutraceuticals were more common in children <8 years. LLT was associated with a mean LDL-C reduction of 25.7%, reaching 50.2% with statin-ezetimibe. Only 26.1% achieved LDL-C goals, with highest rates among those on combination therapy. Conclusions: Despite increased use of pharmacological therapy, therapeutic inertia remains common in paediatric FH, resulting in few children reaching recommended LDL-C targets. These findings highlight the need for earlier intervention, closer follow-up, and optimization of treatment strategies to improve long-term cardiovascular outcomes
Computationally efficient python-based operational modal analysis of structures: Modalyzer
No full textOperational modal analysis (OMA) is a powerful tool in structural health monitoring (SHM), enabling the estimation of dynamic characteristics (natural frequencies, mode shapes, and damping ratios) of structures based on their vibration response under operational conditions. The performance of OMA techniques depends on specific structural characteristics and identification procedure selected. To this aim, a variety of OMA techniques, including enhanced frequency domain decomposition (EFDD), stochastic subspace identification (SSI-COV and SSI-DATA), PolyMAX, and Ibrahim time domain (ITD), are implemented in a new computationally efficient Python library, Modalyzer, developed and presented here for the first time to unify and streamline the application of OMA techniques to different structural contexts. Flexibility and robustness of Modalyzer are demonstrated by applications to three different case-study structures with different conditions and measurement systems, and results obtained by Modalyzer are compared to those obtained by independent calculations and methods for validation purposes. The results highlight strengths and limitations of each method in different structural scenarios, offering guidance on selecting the most suitable OMA technique for specific SHM applications. Moreover, Modalyzer demonstrates significant time efficiency compared to longer computational times of established tools like ARTeMIS Modal, and incorporates user-friendly features further facilitating its adoption within the SHM community
Macro-, micro- and potential toxic elements in commercial Algerian date syrup: Safety aspects and dietary risk assessment
No full textDate syrup, a traditional Saharan product, is attracting attention as a natural sugar alternative for the North
African food sector. Its beneficial dietary and medicinal effects are attributed to its natural antioxidants, sugars,
and minerals. However, poor agricultural practices and environmental factors may cause contaminants to be
released into date syrup. Therefore, mineral content of seven commercial date syrups from various Algerian areas
was analyzed by ICP-MS, including for the first time toxic and potentially toxic elements. Estimated dietary
intakes (EDIs) were calculated for children (1–3 years) and adults, based on a daily serving of 10 g/day and 30 g/
day. The plausibility of chronic non-carcinogenic risks was assessed by calculating the hazard quotient (HQ).
Mineral profile was dominated by K, followed by Ca, Mg, Na, Fe, and Zn in most samples. Pb concentrations were
always below the maximum limit permitted by European Regulation 915/2023 (0.1 mg/kg). EDIs did not exceed
the reference limits. However, since the As percentage absorbed by children in some cases covered 38 % of its
TDI, it is essential to strenghten monitor programs on this natural sweeting agent and establish evidence-based
guidelines for its correct consumption